Yes 100 pulses and 1 pulse

Hi, I have just converted my Orac to later 1983 electrics with a single cable to the later style keyboard, I have all the boards, cables etc that you would require along with manuals for your machine, if you are a student i will let you have what you require to get the machine up and running FOC, wh...

If anyboby is interested i have solved the problem with the screw cutting cycle dropping out. i checked the speed and position sensors on the rear of the spindle, these were ok along with the signals getting through to the control boards, they where switching ok, 0v off 12v on then down to the 0v of...

HI All
has anyone a drawing for an Orac head stock main spindle?
Measuring the existing one is ok but the nose taper is the problem !

i would like the dimentions as making backplates to match the spindle nose taper is causing poblems

any help would be appreciated

Chris

Martin Been a while, xmas hols and all that, not had time on my own in the shed but back on it now, my Orac is 1982, early version with no LED's on the PC board, have checked the signals at the terminals into and out of the board and they are Ok, next step is to trace them throuch the ribbon cable t...

https://www.denfordata.com/downloads/dos ... RCAL-1.zip

https://www.denfordata.com/downloads/dos ... RCAL-2.zip

If you down load these drawings you will find the diagrams of you boards, check out numbers, 1714, 1804, 1849, and 1848

Hi Martin. The machine gets to the screw cutting page and then sets the spindle speed, moves the x axis to the start position and then the program ceases and gives you the manual X,Y axis position screen, the only way to recover is to press the program stop or reset and then reload the program. What...

Anyone got any ideas, my Orac drops out of the program at the start of a threading cycle.
I have checked the spindle speed and position sensors, they seemed ok but have replaced them anyway, they both switch ok and the signal is getting to the control board.

Help please

Chris

Hmmm, 102v on pin 19 think you may be using the wrong ground to measure this, it should be between 0 and 10 volts, this is an isolated supply, the measured voltage will be well above 10 if you use the machine ground. the later boards where different to mine but the principal it the same, i will chec...

Thanks for the offer Keith but that overlay is no good to me, the overlay i require is the one on machine control.

Chris

Hi, i have recently been working on my Orac with spindle speed problems so while its fresh i'll suggest some points to check. On the PC1690 board, bottom one of the stack of three on the left side in the rear of the machine, check the voltage on connector TBF No19 (last terminal to the left of the r...

Hi Torleif Recieved boards thank you, have now sorted all problems apart from thread cutting, pair of sensors on order should be here monday. the Parametric dive board works fine, just needed fine tuning, it will run at 50 rpm no problem, somebody was over zelous with the boost pot. I will do the re...

Have just solved the problem with the zero volts on the speed control signal line, it was the 10volt Zener diode gone short on the PC 1623 speed control overide board, its the diode located between the power input connector and the signal line connector, the cause of it shorting not known but my gue...

If you have the same problem as me, it is the lack of voltage to set the speed, my orac has a similar problem, when you push the motor start button the relay drops in but the spindle will not turn, after some probing with a meter i found there is no speed signal voltage, as this is sitting at 0v the...

Does anyone have or knows where i can obtain an Orac keyboard overlay mine is worn through.
thanks

Chris

Yes, lots of vairables but have to run at fast speed to get the taper as x axis will not step at slow speed over length. has anybody got the original spec for operation ?

Thanks for all your input, i understand that a taper machined on a stepper driven machine will never be the perfect finish. Entering the code, not a problem but while trying to run the job i found that if the feed rate was not high enough the machine would seperate the x and y, first traveling along...

Hi all, new to this forum and CNC. Have recently purchased a 1983 ORAC, not working when i first tried to power it up but have since fixed the power supply probs, i have familierised myself with the programming and got my head round the loss of "0" position when powering up, easy just set the tool o...

Hi Torleif Not to worry, i have the pcb diagram so can work out type of relay and connections. I would still like the the PC1600 and PC1623 if possible, My PC1601 is ok now, its probably the easiest board to repair, had a diode blown in the 24v bridge but all ok now, so that board may be of use to s...

Torleif

Thanks, quick reply, email me, chris15@blueyonder.co.uk please and will give you address details and i would like yours so we can sort out postage

Thanks

Chris